Remove the Particle::normal field

[kolayne]

The normal field is currently a normal of the face the particle is located at. But this is a duplicated information (the normal is stored in the Face object already), neither normal is a property of a particle in any way. So, the field must be removed, the some_particle->map_node->get_face()->get_normal() expression should be used to retrieve a normal given a particle

minds_crawl/src/simulation_objects/Particle.cuh

Lines 150 to 151 in f4dc1c9

	/// Normal to the current face
	SpacePoint normal;